CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 01, 2017	Jun. 25, 2016	Jul. 01, 2017	Jun. 25, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 47,322	$ 43,442	$ 87,283	$ 77,613
Foreign currency translation adjustments:
Unrealized translation gain (loss)	21,551	(2,296)	40,941	217
Derivatives used in Net Investment Hedge, Net of Tax, Period Increase (Decrease)	(550)	0	(1,076)	0
Gain/(loss) on hedging activities:
Amortization cost included in interest expense	18	19	37	38
Other comprehensive income (loss)	21,019	(2,277)	39,902	255
Comprehensive income	68,341	41,165	127,185	77,868
Comprehensive loss (income) attributable to noncontrolling interests	(2,223)	(1,787)	(1,982)	(4,114)
Comprehensive income attributable to Valmont Industries, Inc.	$ 66,118	$ 39,378	$ 125,203	$ 73,754

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of increase (decrease) in the cumulative translation adjustment from gain (loss), after tax, on foreign currency derivatives, that are designated as, and are effective as, economic hedges of a net investment in a foreign entity.

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